The present invention relates to an electric rice cooker and, more particularly, to an electric rice cooker for properly performing auxiliary cooking such as secondary cooking (referred to as a "twice cooking" hereinafter) and/or steaming (ripening) so as to effectively convert beta-starch to alpha-starch after the first cooking (main cooking) of rice and water contained in a cooking pot or kettle is completed.
A technique is already known among those who are skilled in the art in which auxiliary cooking in the "twice cooking" mode is performed to reheat the cooked rice in the cooking kettle, thereby effectively converting beta-starch to alpha-starch and evaporating excessive moisture to cook tasty rice. However, in auxiliary cooking in the "twice cooking" mode, the start time and the operating period of the heater are solely determined by a timer circuit or the like independent of the actual temperature conditions of the cooking kettle. Therefore, when the user wishes to cook a small amount of rice, the bottom portion of the rice gets browned. And, when the user wishes to cook a large amount of rice, beta-starch cannot be sufficiently converted to alpha-starch. As a result, it is very difficult to control the heater in the auxiliary cooking operation of the "twice cooking" mode in accordance with the actual amount of rice and water.